Depending on what solar cell that I want to build it with.How big is that panel? How many would fit on the roof of a trailer?
It's all about scale, environment and options. Get an old exercise bike and put an electric motor where the fan use to be and generate electricity as well as heat.
Not only that but if you have a solar rack, you're going to need a battery rack.but still it's the sort of thing you can measure, save, reinvest etc. until you are off the grid. A battery is gonna cost you a hundred or two bucks.